UPSC Prelims Current Affairs for 13 September 2026

Badri Cattle

September 13, 2026

Badri Cattle Latest News

Scientists in ICAR’s Karnal-based National Dairy Research Institute (NDRI) and Pantnagar-based G B Pant University of Agriculture and Technology have produced a calf of ‘Badri’ cattle breed using Ovum Pick-Up and In Vitro Fertilization (OPU-IVF) technology.

About Badri Cattle

Badri cattle are a small, hardy breed and are designated the state animal of Uttarakhand.
It is also known as “Pahadi”; as they are mainly found in the hilly regions of Uttarakhand.
It is well adapted to hilly terrains and climatic conditions.
Appearance: Its common colour is Black, Brown or Grey, but rarely white colour seen in females. Horns are curved-upward and inward.
- Badri is a small, active and sure-footed animal. Straight forehead with prominent poll, medium to large hump.
Badri is reared mainly for bullock power, milk and manure.
Average milk yield per lactation of Badri cow is 632 kg (range from 547 to 657 kg).
It grazes only on herbs and shrubs available in the mountains, its milk has rich medicinal content and high organic value.
It is the first certified cattle breed of Uttarakhand after the National Bureau of Animal Genetic Resource included it as Badri breed.

Source: PIB

Badri Cattle FAQs

Q1: Where do we find Badri Cattle?

Ans: In the hilly regions of Uttarakhand.

Q2: What is unique about Badri Cattle?

Ans: It is well adapted to hilly terrains and climatic conditions.

Steel Slag

September 13, 2026

Steel Slag Latest News

India has set the Guinness World Record with World’s Longest Steel Slag Road at Raigarh in Chhattisgarh.

About Steel Slag

Steel slag is an industrial byproduct obtained from the steel manufacturing industry.
It is produced in large quantities during steel-making operations that use electric arc furnaces.
It can also be produced by smelting iron ore in a basic oxygen furnace.
Composition: Primarily, slag consists of calcium, magnesium, manganese and aluminium silicates and oxides in various combinations.
The cooling process of slag is responsible mainly for generating different types of slags required for various end-use consumers.

Applications of Steel Slag

Environmental Remediation: It has found use as a barrier material remedy for waste sites where heavy metals tend to leach into the surrounding environment.
Steel slag forces the heavy metals to drop out of solution in water run off because of its high oxide mineral content.
It has been used successfully to treat acidic water discharges from abandoned mines.
It can replace coarse aggregate due to a higher impact and crushing strength, and better anti-skid capacity.
It favours the increase of pH and the availability of nutrients such as Calcium, Magnesium, and Silicon in the soil, which leads to an increase in the absorption of these elements by the plant, favouring crop growth and yield.

Source: News On Air

Steel Slag FAQs

Q1: What is Steel Slag?

Ans: Steel slag is an industrial byproduct obtained from the steel manufacturing industry.

Q2: What is the composition of Steel slag?

Ans: Primarily, slag consists of calcium, magnesium, manganese and aluminium silicates and oxides in various combinations.

Colombo Security Conclave (CSC)

September 13, 2026

Colombo Security Conclave (CSC) Latest News

The three-day Table Top Exercise (TTX) conducted under the aegis of the Colombo Security Conclave (CSC) successfully culminated at Eastern Naval Command (ENC), Visakhapatnam.

About Colombo Security Conclave (CSC)

It is a regional security framework established in 2020.
Member Countries: It comprises India, Bangladesh, Sri Lanka, Maldives, Mauritius, and Seychelles.
Objective: The CSC’s core objective is to promote regional security by addressing transnational threats and challenges of common concern to the member states.
It brings together National Security Advisors (NSAs) and Deputy NSAs of the member countries.
Background
- The CSC, initially known as the Trilateral for Maritime Security Cooperation, evolved out of trilateral meetings between NSAs and Deputy NSAs from India, Maldives, and Sri Lanka, starting in 2011.
- It came to a standstill after 2014 due to rising tensions between India and the Maldives.
- After its revival and rebranding as the CSC in 2020, Mauritius joined the CSC in 2022, while Bangladesh joined in 2024.
- More recently, Seychelles has become the sixth member of the CSC.
Cooperation under the conclave focuses on five pillars:
- Maritime safety and security.
- Countering terrorism and radicalisation.
- Combating trafficking and transnational organised crime.
- Cyber-security and protection of critical infrastructure.
- Humanitarian assistance and disaster relief.
Permanent secretariat: Colombo, Sri Lanka

Source: PIB

Colombo Security Conclave FAQs

Q1: What is Colombo Security Conclave?

Ans: It is a regional security framework established in 2020.

Q2: What are the member countries of Colombo Security Conclave?

Ans: It comprises India, Bangladesh, Sri Lanka, Maldives, Mauritius, and Seychelles.

Ramanathaswamy Temple

September 13, 2026

Ramanathaswamy Temple Latest News

The Prime Minister recently welcomed BRICS leaders against a backdrop featuring Tamil Nadu's iconic Ramanathaswamy temple.

About Ramanathaswamy Temple

It is a Hindu temple dedicated to Lord Shiva located on Rameswaram Island in the state of Tamil Nadu.
History:
- According to the Puranas, Lord Ram arrived at Rameswaram along with Sita and Laxman after his victory over Ravana.
- Ram is believed to have consecrated and worshipped the Shivalinga at the temple to expiate the sin of killing Ravana, who was a Brahmin.
- The name Rameswaram is also linked to this belief. Ramanathaswamy refers to Lord Rameswara, or Eswara, consecrated by Lord Ram.
- The first stone temple was built here by the Chola kings in the 12th century, and additions were made by kings of the Pandya dynasty and the rulers of Vijayanagar.
- The great Krishna Deva Raya of Vijayanagar came here in 1513 after conquering Lanka and made magnificent gifts to the temple.
- The Sethupati kings of Ramnad became the guardians of the temple during the rule of the Nayakas, and they finally completed the temple.
- The Temple is one of the 12 Jyothirlinga temples, where Shiva is worshipped in the form of a Jyotirlingam, meaning "pillar of light".
  - Of the 12 Jyotirlingas, 11 are in the north, and only Ramanathaswamy is in the south.
- It is one of the four Char Dham shrines. The other three are Dwaraka, Puri, and Badrinath, all located in the north.
  - It is the only temple dedicated to Lord Shiva among the four Char Dham shrines.
Architecture:
- The temple is renowned for its stunning Dravidian architecture, characterized by towering gopurams and intricate carvings.
- Like all ancient temples in South India, there is a high compound wall (madil) on all four sides of the temple premises.
- The temple has the longest corridor among all Hindu temples in India. It measures 197 metres from East to West and 133 metres from South to North.
- The temple’s interior features extensive halls between enormous colonnades on platforms over 5 ft.
- The colossal granite walls are marked by intricate carvings and depictions of Hindu deities.
- The temple has 22 holy wells with water believed to have healing properties, used in rituals.

News: TH

Ramanathaswamy Temple FAQs

Q1: Where is the Ramanathaswamy Temple located?

Ans: On Rameswaram Island in Tamil Nadu.

Q2: Which dynasty built the first stone temple at Ramanathaswamy Temple?

Ans: The first stone temple was built here by the Chola kings in the 12th century.

Q3: Which architectural style is prominently associated with the Ramanathaswamy Temple?

Ans: Dravidian architecture.

Q4: Which dynasties made additions to the Ramanathaswamy Temple after the Cholas?

Ans: The Pandya dynasty and the rulers of Vijayanagar.

South Asia Wildlife Enforcement Network

September 13, 2026

South Asia Wildlife Enforcement Network Latest News

Recently, member countries of the South Asia Wildlife Enforcement Network (SAWEN) have adopted the “Kathmandu Declaration” to strengthen regional cooperation against illegal wildlife trade and related transnational organised crime.

About South Asia Wildlife Enforcement Network

It is an intergovernmental law enforcement support body of South Asian countries.
Member Countries: It comprises eight South Asian countries namely: Afghanistan, Bangladesh, Bhutan, India, Maldives, Nepal, Pakistan and Sri Lanka.
It was officially launched in 2011 during the second meeting of South Asia Experts Group on Illegal Wildlife Trade held in Paro, Bhutan.
Aim: SAWEN aims to combat wildlife crime through cooperation, collaboration, coordination, capacity building and communication.
Secretariat: It was formally established in Kathmandu, Nepal, in 2011.
Objectives
- To take initiatives for bringing harmonization and standardization in laws and policies of member countries concerning conservation of wild fauna and flora;
- To document the trend of poaching and illegal wildlife trade, and related threats to the natural biodiversity within and across countries in the region;
- To strengthen institutional responses to combat wildlife crime by promoting partnership with relevant institutions for research and information sharing, training and capacity building, and technical support; and
- To encourage member countries to prepare and implement their National Action Plans to combat wildlife crime and to collaborate towards effective implementation of such plans.
Governance Structure
- It consists of a General Assembly as an apex body of SAWEN comprising ministers of the concerned ministry or his/her senior level government delegate.
- Executive Committee (EC): It consists of all principal focal persons of the member countries.
- Secretariat: It is headed by the Secretary General to perform day to day activities.

Source: News On Air

South Asia Wildlife Enforcement Network FAQs

Q1: What is South Asia Wildlife Enforcement Network?

Ans: It is an intergovernmental law enforcement support body of South Asian countries.

Q2: Where is South Asia Wildlife Enforcement Network's secretariat located?

Ans: Kathmandu, Nepal

Buxa Tiger Reserve

September 13, 2026

Buxa Tiger Reserve Latest News

The West Bengal state government plans to relocate a tigress from a forest in Bihar to the Buxa Tiger Reserve in north Bengal to help revive the tiger population.

About Buxa Tiger Reserve

Location: It is located in the Alipurduar district of West Bengal.
It lies within the Indo-Malayan biodiversity region.
Borders: The northern boundary of the Reserve lies along the international border with Bhutan. The eastern side of the Reserve forms the interstate boundary with Assam, demarcated by River Sankosh.
Physiography: The elevation of this Tiger Reserve ranges from about 60 metres in the plains to nearly 1750 metres in the Himalayan foothills.
It includes Terai, Bhabar and sub-Himalayan ecosystems within a single protected landscape.
Rivers: It is drained by rivers such as Raidak, Sankosh and Jayanti, which originate in Bhutan.
Vegetation: The forests of the reserve can be broadly classified as the ‘Moist Tropical Forest’.
Flora: It supports about 450 tree species, 400 herb species, 250 shrub species, and over 150 orchid species.
Fauna: It is home to elephants, gaur, sambar, spotted deer, barking deer and hog deer etc.

Source: TI

Buxa Tiger Reserve FAQs

Q1: Where is Buxa Tiger Reserve located?

Ans: West Bengal

Q2: Which rivers flows through Buxa Tiger Reserve?

Ans: It is drained by rivers such as Raidak, Sankosh and Jayanti, which originate in Bhutan.

Deltachion ravenshaw

September 13, 2026

Deltachion ravenshaw Latest News

Researchers recently identified a previously undescribed species named Deltachion ravenshaw from the sandy intertidal stretches of the Devi estuary in Puri.

About Deltachion ravenshaw

It is a new clam species.
It belongs to Donacidae, a family of bivalve molluscs of the order Veneroida.
It was discovered from the sandy intertidal stretches of the Devi estuary in Puri, Odisha.
According to the study, 12 Donacidae species are currently recorded in India, seven of them from the Odisha coast.
What makes the discovery particularly interesting is the place where the bivalve was found.
Deltachion species are generally associated with marine environments, while D. ravenshaw was found in the brackish waters of the Devi estuary, where salinity can fluctuate.
Measuring about 6.9 mm, the bivalve has an elongated, triangular shell with a distinctly pointed anterior end.
Its posterior portion has prominent, broad, and flat radial ribs, with fine intersecting lines creating a characteristic lattice-like pattern.
Differences in these shell features, along with the shape of its pallial sinus and ventral margin, help distinguish it from closely related species.

News: TOI

Deltachion ravenshaw FAQs

Q1: What is Deltachion ravenshaw?

Ans: It is a new species of clam.

Q2: From which location was Deltachion ravenshaw discovered?

Ans: The sandy intertidal stretches of the Devi estuary in Puri, Odisha.

Q3: What is unusual about the habitat of Deltachion ravenshaw?

Ans: It was found in the brackish waters of the Devi estuary, despite Deltachion species generally being associated with marine environments.

Q4: What is the characteristic shape of the shell of Deltachion ravenshaw?

Ans: An elongated, triangular shell with a distinctly pointed anterior end.

Fermat’s Last Theorem

September 13, 2026

Fermat’s Last Theorem Latest News

Anthropic recently used its Claude AI to formalise Fermat’s Last Theorem using the Lean language.

About Fermat’s Last Theorem

It is a famous mathematical statement proposed by Pierre de Fermat in 1637 claiming that the equation x^n + y^n = z^n has no integer solutions for n > 2.
This conjecture was noted in the margin of Fermat's copy of "Arithmetica," an ancient Greek text on number theory, where he famously stated that he had a proof too large to fit in the margin.
While solutions exist for n = 1 and n = 2 (known as linear and Pythagorean equations, respectively), the case for (n > 2) remained unsolved for over 350 years, making it one of the most significant unsolved problems in mathematics.
The eventual proof was provided by mathematician Andrew Wiles in 1995, utilizing concepts from the modularity theorem for elliptic curves.
Wiles's work built on earlier contributions from mathematicians like Gerhard Frey and Ken Ribet, who connected concepts related to elliptic curves and Fermat's conjecture.
The theorem has not only resolved a long-standing mystery in mathematics but has also spurred advancements in areas such as algebraic number theory and the study of Diophantine equations.

News: TH

Fermat’s Last Theorem FAQs

Q1: Who proposed Fermat’s Last Theorem?

Ans: Pierre de Fermat.

Q2: What does Fermat’s Last Theorem state?

Ans: The equation x^n + y^n = z^n has no positive integer solutions for n>2.

Q3: Where did Pierre de Fermat write his famous note about the theorem?

Ans: In the margin of his copy of Arithmetica.

Q4: Who provided the proof of Fermat’s Last Theorem?

Ans: Andrew Wiles.

Q5: Which mathematical concept played a crucial role in Andrew Wiles’s proof of Fermat’s Last Theorem?

Ans: The modularity theorem for elliptic curves.

Hasdeo River

September 13, 2026

Hasdeo River Latest News

One student drowned, and two others were recently swept away in the Hasdeo River while they were on a picnic in Chhattisgarh’s Janjgir-Champa district.

About Hasdeo River

It is a major tributary of the Mahanadi River.
It flows through Chhattisgarh state.
Course:
- It originates from a small lake near the Ambikapur town of Surguja district in Chhattisgarh.
- The river flows through Surguja, Korea, and Bilaspur districts and empties into the Mahanadi River near Akaltara in Janjgir–Champa district.
Its course is about 333.0 km long. The river flows through lush green forests, deep valleys, hills, and many small villages.
The Hasdeo basin includes the ecologically important Hasdeo Arand forest region, considered the largest unfragmented forest landscape in Central India.
Hasdeo Bango Dam: The Hasdeo Bango Reservoir is constructed across the river that plays a vital role in irrigation and hydroelectric power generation.
Important Tributaries: Gej and Ahiran

News: TP

Hasdeo River FAQs

Q1: Which major river is the Hasdeo River a tributary of?

Ans: The Mahanadi River.

Q2: In which state does the Hasdeo River flow?

Ans: Chhattisgarh.

Q3: Where does the Hasdeo River originate?

Ans: From a small lake near Ambikapur in Surguja district, Chhattisgarh.

Q4: What is the approximate length of the Hasdeo River?

Ans: About 333 km.

Q5: Which are the important tributaries of the Hasdeo River?

Ans: Gej and Ahiran.

Mayun Island

September 13, 2026

Mayun Island Latest News

Yemen’s Iranian-backed Houthi rebels recently captured the strategic island of Mayun in the Bab el-Mandeb Strait at the entrance to the Red Sea.

About Mayun Island

Mayun Island, also known as Perim Island, is a small volcanic island belonging to Yemen, located in the strategically important Bab el-Mandeb Strait, at the southern entrance to the Red Sea.
Although rocky and just 13 sq.km. in area, the volcanic island rises as high as 65 m and overlooks the strait near its narrowest point, about 26 km wide.
Perim Island actually splits the Bab el-Mandeb Strait into two smaller channels.
The importance of the small island grew with the advent of the Suez Canal, which connected the Mediterranean Sea and the Arabian Sea through the Red Sea and allowed global shipping routes to bypass the lengthy route around Africa.
As steps were taken to begin the construction of the canal, the British seized the island in 1857 and established a coaling station, which later went bankrupt in 1935.
For many years, from 1857 to 1967, Perim Island was part of the British Empire.
Perim Island became part of independent Yemen (Aden) in 1967.
The Bab el-Mandeb Strait became a vital chokepoint along the new route, and Perim Island’s position within the strait gave its occupier command over the eastern channel and a measure of control over its western channel.
It has a deep and large natural harbor on its southwestern side and a military airfield in the north.

News: NOA

Mayun Island FAQs

Q1: What is another name for Mayun Island?

Ans: Perim Island.

Q2: Which country does Mayun Island belong to?

Ans: Yemen.

Q3: In which strait is Mayun Island located?

Ans: The Bab el-Mandeb Strait.

Q4: Where is Mayun Island located in relation to the Red Sea?

Ans: At the southern entrance to the Red Sea.